Personnel scheduling is an important and challenging task that arises in a variety of application areas. Scheduling quality, however, strongly depends on the results of the preceding activities of staffing and shift design. This paper presents a novel approach that integrates staffing, shift design and scheduling into one optimization problem for the first time, providing a holistic view of the workforce planning process. By applying an evolutionary multi-objective bilevel algorithm, the three objectives staffing costs, number of shifts and scheduling quality are optimized simultaneously. The experimental results show that the presented holistic approach is suitable to support decision making regarding staffing as well as shift design by showing the decision maker tradeoffs between different solution alternatives. Furthermore, applying the holistic approach reveals new promising solution areas and valuable individual solutions, which would not have been found when optimizing sequentially.